<?php
/**
  * wechat php test
  * update time: 20141008
  */

//define your token
define("TOKEN", "WEIXIN_TEST");
$wechatObj = new wechatCallbackapiTest();
$wechatObj->valid();
$wechatObj->responseMsg();
exit;

class wechatCallbackapiTest
{
    public function valid()
    {
        $echoStr = $_GET["echostr"];

        //valid signature , option
        if($this->checkSignature()){
            echo $echoStr;
            //exit;
        }
    }

    public function responseMsg()
    {
        //get post data, May be due to the different environments
        $postStr = $GLOBALS["HTTP_RAW_POST_DATA"];

        //extract post data
        if (!empty($postStr)){
                
                $postObj = simplexml_load_string($postStr, 'SimpleXMLElement', LIBXML_NOCDATA);
                $fromUsername = $postObj->FromUserName;
                $toUsername = $postObj->ToUserName;
                $keyword = trim($postObj->Content);
                $time = time();
                $textTpl = "<xml>
                            <ToUserName><![CDATA[%s]]></ToUserName>
                            <FromUserName><![CDATA[%s]]></FromUserName>
                            <CreateTime>%s</CreateTime>
                            <MsgType><![CDATA[%s]]></MsgType>
                            <Content><![CDATA[%s]]></Content>
                            <FuncFlag>0</FuncFlag>
                            </xml>";     
                if($postObj->MsgType == "event" ){
                    $contentStr = "触发了一个事件"."\n";
                    if($postObj->Event == "CLICK"){
                        $contentStr .= "这是一个click事件"."\n";
                        if($postObj->EventKey == "V1001_TODAY_MUSIC")
                            $contentStr .= "click事件的key是".$postObj->EventKey."名称为{今日歌曲}"."\n";
                    }

                     $msgType = "text";                    
                     $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
                     echo $resultStr;
                     exit;

                }        
                if(!empty( $keyword ))
                {
                    $msgType = "text";
                    $contentStr = "欢迎关注本公众号"."\n";
                    $contentStr .= "Welcome to wechat world!";
                    $resultStr = sprintf($textTpl, $fromUsername, $toUsername, $time, $msgType, $contentStr);
                    echo $resultStr;
                }else{
                    echo "Input something...";
                }

        }else {
            echo "";
            exit;
        }
    }
        
    private function checkSignature()
    {
        $signature = $_GET["signature"];
        $timestamp = $_GET["timestamp"];
        $nonce = $_GET["nonce"];
        $token = TOKEN;
        $tmpArr = array($token, $timestamp, $nonce);
        sort($tmpArr, SORT_STRING);
        $tmpStr = implode( $tmpArr );
        $tmpStr = sha1( $tmpStr );
        
        if( $tmpStr == $signature ){
            return true;
        }else{
            return false;
        }
    }
}

?>